Agents, reducing

I began graduate studies at the University of Chicago in 1936. At that time, the structure of diborane was a subject of considerable study and 

I soon discovered that simple aldehydes and ketones react rapidly with diborane at 0° C. Hydrolysis then produces the corresponding alcohol. 

My thesis was completed in 1938 and the results were published in 1939 Hydrides of Boron. XI. The Reaction of Diborane with Organic Compounds Containing a Carbonyl Group (3). 

Interest in this development among organic chemists was minimal. Diborane was a chemical rarity at the time, available only in milligram quantities through complex procedures. 

Most recently, various halide ions were utilized for shape control. Bromide ions were used to synthesize Rh nanocubes [29]. Nal was added to synthesize PtcPdi c nanocubes, whereas substituting Nat with NaCl produced PtPd nanooctahedra [30]. 

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Andrews deration An important titration for the estimation of reducing agents. The reducing agent is dissolved In concentrated hydrochloric acid and titrated with potassium iodale(V) solution. A drop of carbon tetrachloride is added to the solution and the end point is indicated by the disappearance of the iodine colour from this layer. The reducing agent is oxidized and the iodate reduced to ICl, i.e. a 4-eiectron change. 

Benedict solution Aqueous solution of Na2C03, CuSO, and sodium citrate used for testing for reducing agents, particularly sugars, which give red-yellow colours or precipitates. 

Chromium(IJ) chloride, chromous chloride, CrCl2- White solid (Cr plus HCl gas) dissolving to give a blue solution. Forms hydrates, widely used as a reducing agent. 

Europium(TTI) salts are typical lanthanide derivatives. Europium(ll) salts are pale yellow in colour and are strong reducing agents but stable in water. EuX2 are prepared from EuX -hEu (X=C1, Br, I) or EuFa + Ca EuCl2 forms a dihydrale. EUSO4 is prepared by electrolytic reduction of Eu(III) in sulphuric acid. Eu(II) is probably the most stable +2 stale of the lanthanides... 

Germanium chlorides. GeCl4, m.p. —49°C, b.p. 86" C (Ge plus CI2) is hydrolysed by water. GeClj, colourless reducing agent (GeCU plus Ge). 

NH4)2Fe(S04)2,6H20. Pale green crystalline solid used as a standard reducing agent (e.g. for KMn04). More stable than FeS04. 

LiAKOBujaH. A selective reducing agent for converting RCOCl to aldehydes and reducing steroid ketones. See aluminium hydride. 

Hi at 500" C. Stable crystalline compound, gives LiOH and Hi with water (may ignite in moist atmosphere). Used as a source of Hi, as a reducing agent, and for the preparation of hydrides. 

Hypophosphorous acid, H3PO2, H2P(0)0H. A monobasic acid. Ba(H2P02)2 is formed when white phosphorus is dissolved in Ba(OH)2 solution. H3PO2 and its salts are strong reducing agents. 

Phosphorous acid, H3PO3, HP(0)(0H)2-A dibasic acid (PCI3 plus cold water), strong reducing agent. 

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